
On 15.01.14 09:59, Russell Coker wrote some quite reasonable specs for an embedded Linux platform - plus a scary (expensive & harder to source) temperature spec. There are about 106,000 of this out there, so far: http://beagleboard.org/products/beaglebone%20black It is beginning to be used for CNC, with RTAI or Xenomai under Ubuntu, for fast real-time performance, but most users just use a plain Linux distro. It has a 1 GHz cpu, and it seems to match on memory, has one 10/100 ethernet, 69 GPIO pins, and a PRU which can be programmed to fiddle the IO at great speed. There's one serial port, plus more on the expansion connector. The 6-layer board makes it quite small - possible because it dissipates under 2.5W. Summary at: http://elinux.org/Beagleboard:BeagleBoneBlack#BeagleBone_Black_Description Now 0 - 70°C _component_ temperature would be just commercial temperature grade. 70°C ambient is a real problem. This document: http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDsQF... mentions "case temperatures greater than 60 C", which is 35 - 40°C above ambient = 105 - 110°C at 70°C ambient. That would require military grade componentry. (Industrial is only good to 85°C case temperature.) Still, for $45, it's not a bad embedded Linux platform at all. Sit it on a Peltier-effect cooler, and you'd add 25°C margin. That'd perhaps double the price, and bring power consumption up to 50W or so. Add a power FET and a thermistor, and the Beaglebone's A/D converter and a digital I/O could provide the thermostat function. It take "capes" (daughter boards analogous to Arduino "shields"), so it's easy to design a board in Eagle, email the file to Malaysia, and have a board back in less than a week, for next to no money. Erik -- For the month of December 2013, 57.4% of all the electricity consumed in Denmark was generated by wind turbines. Over the whole year, it was 33.8%, and on 21st December, the wind turbines produced over 100% of Denmark's electricity consumption. - http://epn.dk/brancher/energi/alternativ/ECE6403277/danske-vindmoeller-skriv...